-LRB- CNN -RRB- -- A Florida exterminator and father of four children adopted from Florida 's foster care system has told police that a body found in the pest-control truck he was driving is one of them -- his 10-year-old daughter , authorities said Wednesday .

Jorge Barahona , 53 , already faces a charge of aggravated child abuse for injuries to the dead girl 's twin , Victor , who was also found in the truck , which was parked on the side of I-95 near West Palm Beach , Florida , officials said .

According to a probable-cause affidavit filed by the West Palm Beach Police Department , a roadside assistance ranger with the Florida Department of Transportation stopped to check the red Toyota pickup Monday around 5:30 a.m. and found the 10-year-old boy inside next to an open gas can .

The boy `` appeared to be in respiratory distress and -LRB- was -RRB- trembling '' and his clothing `` was soaked with an unknown chemical , '' the affidavit said .

The ranger then found Barahona on the ground beside the truck and called for help .

The boy was hospitalized in intensive care with severe burns to his abdomen , upper thighs and buttocks , the affidavit said . While examining the boy , doctors noted he had sustained previous injuries , including a broken collarbone , a broken arm , scarring to his buttocks and lower abdomen , and ligature marks on both wrists , police said .

After Barahona and his son were taken to a hospital , a worker decontaminating the truck discovered the body of the girl , wrapped in a plastic bag , the document said .

Barahona told police he was distraught over the death of his daughter , and had intended to commit suicide by dousing himself with gasoline and setting himself afire , the affidavit said . Barahona said he did n't go through with his suicide plan because his son was with him , the document added .

`` Basically , to paraphrase , he was stating that he placed his daughter in a plastic bag being distraught over her death , '' West Palm Beach Police Spokesman Chase Scott told reporters . `` He drove here from South Florida accompanied by his son , Victor . He then pulled off to the side of the road saying that he poured gas on his self , intending to light himself on fire . His son 's head was in his lap and he decided , after giving his son some sleeping pills , that he was n't going to do that . ''

Barahona told police that he doused himself with gasoline and inadvertently got some on the boy , Police Capt. Mary Olsen said .

But , she added , the man 's story does n't add up -- there was no gasoline on the boy . Instead , he was covered with another chemical whose composition had yet to be determined . `` That 's why we 're still treating this as a hazmat -LRB- hazardous materials case -RRB- , '' she said .

Scott said the chemicals were so potent that staff caring for the boy at the hospital became ill as well , he said .

Victor , who was transferred Wednesday morning to a specialized burn unit at Miami 's Jackson Memorial Hospital , has not been able to talk to investigators because he is on a breathing tube , she said .

Olsen said police would decide how to charge Barahona further once the autopsy on his daughter determines her cause of death .

Asked whether Barahona has expressed remorse , she said , `` He feels remorse , but we 're not getting consistent statements with what we 're seeing in our evidence . '' She added , `` It 's a complex case . ''

At a hearing Wednesday in Miami attended by Barahona 's wife , Carmen , a judge ordered that the remaining two children in the home be placed in foster care .

Florida 's Department of Children and Families had opened a child protection investigation within the past few days to look into a complaint involving the Barahona family , and it was n't the first such complaint , spokesman Mark Riordan said .

Reporters in the courtroom Wednesday heard tales of abuse , mainly concerning the twins , from state officials and experts . The caller to the child protection hotline in the latest case reported that the twins were routinely locked in a bathroom for long periods of time and had been bound with tape , the court heard . The story was corroborated by interviews with the other two children in the home , officials said in court .

An investigator told the court that she had showed up last Friday night at the family 's home but had not seen the children . Instead , she said , she had left the family 's house after speaking with Carmen Barahona , planning to return on Monday . Asked why she had not planned to return sooner , she said , `` I 'm not allowed to do investigations on a weekend . ''

However , a spokesman for the department , John Harrell , said it is the job of investigators to follow through immediately or refer to someone else in the department to follow through when a matter is urgent .

CNN 's Kim Segal , Shawn Nottingham and John Zarrella contributed to this report

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NEW : Barahona charged with aggravated child abuse

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The couple 's remaining two children have been placed in foster care , court officials said

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The girl 's body was in a plastic bag , an affidavit said

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Jorge Barahona 's son is in intensive care , police say